“If she were a constant companion, I’m not sure the fans would enjoy that so much.”

River Song is returning to Doctor Who this Christmas – but Alex Kingston doesn’t expect to stick around as a full-time companion.
Kingston told press that she won’t be jumping aboard the TARDIS as Jenna Coleman’s replacement.

“I think the beauty of a character like River Song is that she’ll come in for an adventure and then she goes off again, and I think that’s what the fans love,” the actress said.
“If she were a constant companion, I’m not sure the fans would enjoy that so much – and it would take away the opportunity for someone else to become the companion.

“River is already established, so why not keep her in that respect and bring in a new companion? Because then you’ve got more people to interact with and play with.
“I’d love it if she came back again. But I think it works best the way Steven [Moffat]’s always interpreted their relationship.”

So if not a full-time post, how about a River spinoff?
“After the 9 ‘o’ clock watershed? With Captain Jack? Might be naughty!”

Kingston was a popular choice for Doctor Who fans in Digital Spy’s poll of potential companion candidates.
However, showrunner Moffat has told DS that the next companion – replacing Coleman’s long-standing Clara – will be an entirely new character.

The Doctor Who festive special, ‘The Husbands of River Song’, will air on Christmas Day (Friday, December 25) at 5.15pm on BBC One.